LXR linux/drivers/s390/cio/css.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _CSS_H
   3#define _CSS_H
   4
   5#include <linux/mutex.h>
   6#include <linux/wait.h>
   7#include <linux/workqueue.h>
   8#include <linux/device.h>
   9#include <linux/types.h>
  10
  11#include <asm/cio.h>
  12#include <asm/chpid.h>
  13#include <asm/schid.h>
  14
  15#include "cio.h"
  16
  17/*
  18 * path grouping stuff
  19 */
  20#define SPID_FUNC_SINGLE_PATH      0x00
  21#define SPID_FUNC_MULTI_PATH       0x80
  22#define SPID_FUNC_ESTABLISH        0x00
  23#define SPID_FUNC_RESIGN           0x40
  24#define SPID_FUNC_DISBAND          0x20
  25
  26#define SNID_STATE1_RESET          0
  27#define SNID_STATE1_UNGROUPED      2
  28#define SNID_STATE1_GROUPED        3
  29
  30#define SNID_STATE2_NOT_RESVD      0
  31#define SNID_STATE2_RESVD_ELSE     2
  32#define SNID_STATE2_RESVD_SELF     3
  33
  34#define SNID_STATE3_MULTI_PATH     1
  35#define SNID_STATE3_SINGLE_PATH    0
  36
  37struct path_state {
  38        __u8  state1 : 2;       /* path state value 1 */
  39        __u8  state2 : 2;       /* path state value 2 */
  40        __u8  state3 : 1;       /* path state value 3 */
  41        __u8  resvd  : 3;       /* reserved */
  42} __attribute__ ((packed));
  43
  44struct extended_cssid {
  45        u8 version;
  46        u8 cssid;
  47} __attribute__ ((packed));
  48
  49struct pgid {
  50        union {
  51                __u8 fc;        /* SPID function code */
  52                struct path_state ps;   /* SNID path state */
  53        } __attribute__ ((packed)) inf;
  54        union {
  55                __u32 cpu_addr  : 16;   /* CPU address */
  56                struct extended_cssid ext_cssid;
  57        } __attribute__ ((packed)) pgid_high;
  58        __u32 cpu_id    : 24;   /* CPU identification */
  59        __u32 cpu_model : 16;   /* CPU model */
  60        __u32 tod_high;         /* high word TOD clock */
  61} __attribute__ ((packed));
  62
  63struct subchannel;
  64struct chp_link;
  65/**
  66 * struct css_driver - device driver for subchannels
  67 * @subchannel_type: subchannel type supported by this driver
  68 * @drv: embedded device driver structure
  69 * @irq: called on interrupts
  70 * @chp_event: called for events affecting a channel path
  71 * @sch_event: called for events affecting the subchannel
  72 * @probe: function called on probe
  73 * @remove: function called on remove
  74 * @shutdown: called at device shutdown
  75 * @prepare: prepare for pm state transition
  76 * @complete: undo work done in @prepare
  77 * @freeze: callback for freezing during hibernation snapshotting
  78 * @thaw: undo work done in @freeze
  79 * @restore: callback for restoring after hibernation
  80 * @settle: wait for asynchronous work to finish
  81 */
  82struct css_driver {
  83        struct css_device_id *subchannel_type;
  84        struct device_driver drv;
  85        void (*irq)(struct subchannel *);
  86        int (*chp_event)(struct subchannel *, struct chp_link *, int);
  87        int (*sch_event)(struct subchannel *, int);
  88        int (*probe)(struct subchannel *);
  89        int (*remove)(struct subchannel *);
  90        void (*shutdown)(struct subchannel *);
  91        int (*prepare) (struct subchannel *);
  92        void (*complete) (struct subchannel *);
  93        int (*freeze)(struct subchannel *);
  94        int (*thaw) (struct subchannel *);
  95        int (*restore)(struct subchannel *);
  96        int (*settle)(void);
  97};
  98
  99#define to_cssdriver(n) container_of(n, struct css_driver, drv)
 100
 101extern int css_driver_register(struct css_driver *);
 102extern void css_driver_unregister(struct css_driver *);
 103
 104extern void css_sch_device_unregister(struct subchannel *);
 105extern int css_register_subchannel(struct subchannel *);
 106extern struct subchannel *css_alloc_subchannel(struct subchannel_id);
 107extern struct subchannel *get_subchannel_by_schid(struct subchannel_id);
 108extern int css_init_done;
 109extern int max_ssid;
 110int for_each_subchannel_staged(int (*fn_known)(struct subchannel *, void *),
 111                               int (*fn_unknown)(struct subchannel_id,
 112                               void *), void *data);
 113extern int for_each_subchannel(int(*fn)(struct subchannel_id, void *), void *);
 114void css_update_ssd_info(struct subchannel *sch);
 115
 116struct channel_subsystem {
 117        int cssid;
 118        struct channel_path *chps[__MAX_CHPID + 1];
 119        struct device device;
 120        struct pgid global_pgid;
 121        struct mutex mutex;
 122        /* channel measurement related */
 123        int cm_enabled;
 124        void *cub_addr1;
 125        void *cub_addr2;
 126        /* for orphaned ccw devices */
 127        struct subchannel *pseudo_subchannel;
 128};
 129#define to_css(dev) container_of(dev, struct channel_subsystem, device)
 130
 131extern struct channel_subsystem *channel_subsystems[];
 132
 133/* Dummy helper which needs to change once we support more than one css. */
 134static inline struct channel_subsystem *css_by_id(u8 cssid)
 135{
 136        return channel_subsystems[0];
 137}
 138
 139/* Dummy iterator which needs to change once we support more than one css. */
 140#define for_each_css(css)                                               \
 141        for ((css) = channel_subsystems[0]; (css); (css) = NULL)
 142
 143/* Helper functions to build lists for the slow path. */
 144void css_schedule_eval(struct subchannel_id schid);
 145void css_schedule_eval_all(void);
 146void css_schedule_eval_all_unreg(unsigned long delay);
 147int css_complete_work(void);
 148
 149int sch_is_pseudo_sch(struct subchannel *);
 150struct schib;
 151int css_sch_is_valid(struct schib *);
 152
 153extern struct workqueue_struct *cio_work_q;
 154void css_wait_for_slow_path(void);
 155void css_sched_sch_todo(struct subchannel *sch, enum sch_todo todo);
 156#endif
 157